The Olive Oil Police!

Most "Italian" olive oil in fact comes from countries like Spain, Morocco, and Tunisia, passing through refineries in Italy. Some cut the olive oil with cheaper oils; some produce fake olive oil using beta-carotene and chlorophyll.

A study at University of California, Davis in 2010 found that 69% of "extra virgin" imported olive oil didn't meet the smell and taste standard for extra virgin oil. "The study suggested that the substandard samples had been oxidized; had been adulterated with cheaper refined olive oil; or were of poor quality because they were made from damaged or overripe olives, or olives that had been improperly stored or processed — or some combination of these flaws." The study didn't estimate how much olive oil in the U.S. is poor quality vs. actually adulterated or outright counterfeit.

And yes, there's a branch of the Italian Carabinieri trained to literally use the smell test to detect bad oil. (Lab tests are apparently easy to fool. Unfortunately, well-connected producers are rarely prosecuted.)

"Apparently, the counterfeiters have been at it so long that some people with trained palates can't even pick out the fake oils by taste alone. The biggest thing you'll miss is all the healthy benefits of olive oil's monounsaturated fatty acids, which are known to reduce cholesterol levels and may help normalize blood clotting and insulin levels....

Your best bet for protecting yourself from fake olive oil is to cut out the middleman and buy known brands that refine their own oil and don't purchase it in bulk from third-party refineries that may adulterate the product."

My wife has been using Bertolli for a while. Can't say that either of us have any complaints (other than being duped about its "extra virgin" status). That begs the question, though: how much do you have to spend to get the real deal and do ANY discount olive oils pass muster?

Yes! According to this article, Kirkland Signature Organic Extra Virgin Olive Oil (Costco's house brand) is fine; all three samples passed UCDavis's smell/taste and chemistry tests.

(I read elsewhere that Costco maintains "premium" quality standards throughout its Kirkland Signature brand; Bumble Bee had to produce higher-quality tuna for labeling as Kirkland Signature than for its own advertised label!)